C(sp3)–H dehydrogenation and C(sp2)–H alkoxy carbonylation of inactivated cyclic amines towards functionalized N-heterocycles. Issue 28 (24th March 2017)

• Record Type: Journal Article
• Authors: He, Yan; Wang, Fang; Zhang, Xinying; Fan, Xuesen
• Is Part Of: Chemical communications. Volume 53:Issue 28(2017)
• Page Start: 4002
• Page End: 4005
• Publication Date: 2017-03-24
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1039/c6cc10227a
• Languages: English
• ISSNs: 1359-7345

Abstract

Abstract : A novel and efficient synthesis of tetrahydropyridine-, dihydropyrrole-, and tetrahydroazepine-3-carboxylates via cascade reactions of cyclic amines with CO and alcohols is presented. To our knowledge, this should be the first example in which functionalized N-heterocycles were prepared through Pd-catalyzed C(sp 3 )–H dehydrogenation and C(sp 2 )–H carbonylation of cyclic amines. Abstract : A novel and efficient synthesis of tetrahydropyridine (THP)-, dihydropyrrole (DHP)-, or tetrahydroazepine (THA)-3-carboxylates via cascade reactions of inactivated cyclic amines with CO and alcohols is presented. To our knowledge, this should be the first example in which functionalized N-heterocycles were prepared directly from Pd-catalyzed C(sp 3 )–H dehydrogenation and C(sp 2 )–H carbonylation of saturated cyclic amines. Moreover, the DHP-3-carboxylates thus obtained could readily undergo an oxidative aromatization to give pyrrole-3-carboxylates by using O2 as a green oxidant. Notable features of the methods developed herein include simple substrates, high efficiency and excellent atom-economy, mild reaction conditions, and broad substrate scope.